"eval" in ghc(i)?

[Simon Peyton-Jones]

| /me ponders an api ...
| 
| Something like:
| 
|     > GHC.Top.init
|     > f <- run "let add1 x = x + 1"
|     > f 7
|     8

GHC's api has a clear notion of a "session" that I believe we should not
lose.  So it'd be

	> s <- GHC.Top.init
	> f <- run s "\x -> x+1"
	> f 7

Here s is the session handle.  Modulo that, I think it'd just be a
question of setting up suitable defaults to get this API

Simon